Interior lighting systems for motor vehicles can be used as room lighting or as ambient light in the interior of a motor vehicle, wherein these lighting systems may be realized in the form of background lighting and/or used for illuminating individual objects, and wherein this illumination may have a purely aesthetic function or also a technical function such as, e.g., simplifying the process of locating and/or operating different components in the interior of the motor vehicle. In the past, it was common practice to use light bulbs for the interior lighting, namely for lighting, as well as for the illumination of individual objects. LEDs and electroluminescent films are nowadays increasingly used for lighting purposes. It is furthermore known to integrate and embed lighting systems into interior trim elements, wherein such an integration is subject to different restrictions such as the heat output of the lighting systems, the susceptibility of the lighting systems to damages, as well as the accommodation of the lighting systems such that they are inconspicuous and integrate well into the interior trim elements.
EP 2 228 258 A2 of the applicant describes the integration of LEDs and associated drive electronics into interior trim elements. A relatively thin printed LED background lighting component with integrated diffuser is incorporated into an interior trim element during a molding process. The actual light source of the LED background lighting component is hidden behind a fabric surface or a screen or directly forms the outer surface of the interior trim element in order to provide lighting. A similar arrangement is disclosed in DE 10 2010 036 795 A1.
US RE 42 340 E describes an interior lighting system for a motor vehicle that utilizes electroluminescent panels arranged between a carrier substrate and a cover layer, wherein the cover layer is transparent. Recesses for accommodating the electroluminescent panel may be provided in the carrier substrate or the cover layer such that the panel does not stand out against the material of the cover layer and is imperceptible from outside.
EP 2 233 366 A1 also describes an interior trim element with a backlit decorative layer, wherein a light-conducting layer is arranged between a carrier substrate and the decorative layer.
In lighting systems that are integrated into the interior trim of a motor vehicle, the light-conducting and light-emitting layer is always located between a carrier substrate that defines the contour of the interior trim and a cover layer consisting of one or more layers. Since the light-emitting layer is embedded between the carrier substrate and the cover layer, the light-emitting layer is essentially imperceptible in the deactivated state and protected between the cover layer and the carrier substrate. However, these systems also have a number of disadvantages. In order to connect the light-emitting layer to the associated drive electronics and/or light sources and/or to supply the light-emitting layer with power, connections of the light-emitting layer are integrated into the carrier substrate or routed on the rear side of the carrier substrate such that they are accessible in order to be serviced and replaced, if so required. Connections of this type are described in DE 10 2010 036 795 A1.
DE 10 2013 100 941 A1 of the applicant describes an interior trim element for a motor vehicle having a carrier component that defines the contour of the interior trim element, a cover layer that is applied onto the front side of the carrier component and a light-emitting layer that is arranged on the rear side of the carrier component, wherein the carrier component and the cover layer are transparent. Due to the arrangement of the light source on the rear side of the carrier component, it is protected better than in the above-described prior art.
An objective can be seen in disclosing an interior trim element for a motor vehicle that makes it possible to broaden the potential applications of the interior trim element.